Process of preserving silk weighted with metal salts.



hereby declare the following to'be a light, but also after more UNITEDSTATES ATENT oEEioE.

OTTO MEISTER, OF ZURICH, SWITZERLAND, ASSIGNOR TO WEIDMANN SILK DYEINGCOMPANY, OF PATERSON,

NEW JERSEY, .A CORPORATION or NEW JERSEY;

PROCESS OF PRESERVING SILK WEIGHTED WITH METAL SALTS.

Patented May 2, 1911. 585,311. Divided and this application filedNovember 21, 191,0; Serial no. 593,380.

To all whom it may concern: 2 Be it known that I OTTO MEISTER, a citizenof the Republic of Switzerland, residing in Zurich, Switzerland, haveinvented certain new and useful Process of Pre erving Silk Weighted withMetal Salts; and lf u (1110 7 clear, and, exact description of theinvention, such as will enable others skilled in the art to which itappertains to make and use the same.

My present application is a division of my application for LettersPatent of the United:

4, 1910, Serial No.

States filed. October 585311. e

It is well known that the weighting of color-dyed silk with theso-called tin-phosphate-silicate charge is accompanied by a considerablerisk. of reducing thev strength and elasticity of the silk filaments sothat the goods manufactured therefrom, especially if subjected to theinfluence of heat or or less length of time merely in storage, willbecome so weak and rotten that they are substantially use less. As aremedy for this, or at least to diminish the likelihood of itsoccurrence, it-is a well-known expedient to treat the tinweighted silkwith rhodan compounds. This treatment, however, involves the disadvanderthe influence of heat and quite as readily reconverted to its originalform. But this substance, like hydrochinon or hydrochinonsulfonic acid,also heretofore suggested, is-

too expensive;

My new process has for its purpose to give to the weighted silk theproperty of more effectively resisting deterioration, in storage and "inuse, due to the influences of light, air and humidity, withoutdetracting from the feel and luster of the silk or making it sensitiveto iron, with accompanying reddish tinge.

The improved process consists in treating the silk with the body whichresults from the reaction of ammonia and formaldehyde--hexamethylenetetramin, with the formula (CH N,-from one to five percent, thereo f being used, and] which may be added either to the finalwash orin the earlier stages of the mordanting or dyeing processes, al-

though it 1s to be understood that good re sults may be obtained withoutstrict adherence to this procedure; for instance, the body referred tomay be applied at any stage of the mordanting and'dyeing process, or tothe silk threads or even to thegoods after the process of manufacturingthe same is completed. The body referred t0-hexamethylenetetraminand theother aldehyde ammonias are equally operative in preserving Weightedsilk.

I claim:-

In the art of weighting silk by the-use of metal salts, the process silkwhich consists in treating the same with the body which results from'thereaction of ammonia and formaldehyde, substantially as described. I

In testimony whereof,I have hereunto set my hand this 7th day ofNovember, 1910.

OTTO MEISTER. Witnesses EMIL MEISTER, J onus JAGGLI.

of preserving the

